Medem Inc., the for-profit Internet company backed by the American Medical Association and other physician groups, plans to launch a new service Monday that will enable doctors to charge patients for online "visits."

If it catches on, the new service could diminish a view among some patients that doctors have been slow to adopt Internet technology to make communications easier. In numerous patient surveys, the majority say they want to seek advice from their doctors via e-mail. Doctors, however, are less enthusiastic: Recent studies find less than one-quarter of surveyed doctors report using e-mail with patients.

A study at the University of Michigan Health System in Ann Arbor, published in the May issue of the American Journal of Managed Care, suggests that e-mail can actually increase the workload of doctors' offices, and recommends that doctors educate patients about when its use is "appropriate." Medem, however, says its online consultation feature lets doctors manage e-mail efficiently and addresses physicians' biggest concerns: potential liability and the lack of payment.

San Francisco-based Medem says the service meets so-called eRisk guidelines for online medicine, which have been endorsed by 33 malpractice carriers, the AMA and other medical societies. Medem's service also allows patients to pay with a credit card, which means doctors won't have to handle extra work without compensation. But it will largely be out of patients' own pockets, at least for now: Outside of a few experiments by companies and insurers, e-mail consultations aren't reimbursed.

Other Internet medical firms have drawn scrutiny from physician groups and regulators because they offer patients anonymous consultations with doctors they have never met, a practice deemed ethically questionable. But this Medem service is meant for physicians to use with patients already under their care. Doctors pay Medem $2.50 per online visit, if the doctor bills the patient for it. A simple question might not result in a patient fee.

The consultation service expands Medem's "secure messaging" option, which lets patients request appointments and prescription refills and ask brief questions. Roughly 10% of Medem's 80,000 doctor users already offer the messaging option, which patients use free of charge. (Less than 5% of the doctors in Medem's network are overseas, in Europe, Asia and Latin America.) Unlike standard e-mail, secure messaging is encrypted to protect privacy; if it goes awry by mistake, the message appears garbled.

The new consultation service allows patients -- for a fee -- to ask detailed clinical questions and receive detailed answers, and possibly a prescription authorization for minor ailments. Physicians can field requests directly, or designate a nurse or colleague to screen them first. Doctors set the fees; physicians interviewed said they expect to charge $20 to $30 a visit.

Here's how it works: Once doctors enroll in the service through Medem, patients register with their doctor and obtain a password. (Doctors can choose to offer it to all patients at once, or offer it on a patient-by-patient basis.) Patients must agree to the doctor's terms of service, which spell out the cost of the service and the expected length of time within which the doctor will respond.

Luke Megna, a family and sports-medicine doctor in Richland, Wash., started offering online consultations as part of a limited Medem test three months ago and now fields about five requests a week. He says he typically responds within 24 hours.

Leon Dotson, 80 years old, a Richland retiree, used the service to follow up with Dr. Megna after visiting the emergency room for an attack of vertigo. He finds online communication convenient: There's no delay in securing an appointment, as there sometimes is with an office visit. "These are professional people and you are taking their time," he says, "so you should expect to pay for this."

Lynne Carr Columbus, a Tampa, Fla., pain-management specialist, says the online option is useful for her patients, many of whom take drugs for chronic pain and need periodic monitoring for side effects and proper dosage. It's often difficult for patients with back pain, for example, to sit and wait in the office. "So we let them do two online consults, and then come in for the third one to be seen in person," she says. "It wouldn't work for emergency situations; it's for routine consults and follow-ups."